Police seized a number of firearms, including these guns, in a year-long investigation that started in Edmonton. (CBC)

A year-long gang investigation that started in Edmonton has led police to lay 86 charges against 12 people, a body of police organizations announced Thursday.

Officers seized 28 firearms; seven kilograms of cocaine worth up to $250,000; 3,000 ecstasy tablets; $300,000 in cash; and stolen property when they executed several search warrants at a number of Edmonton homes last week.

Police allege the individuals are members of a gang with links to Edmonton, St. Albert, Red Deer and Grande Prairie, Alta., as well as Vancouver.

"The group that we're investigating is one criminal organization but it is fair to say they conduct business with a broad spectrum of other gangs and organized crime groups," RCMP Insp. Bob Simmonds said.

Police said they also seized gang paraphernalia, some with "WBP" printed on it, which stands for White Boy Posse, a Edmonton gang.

Investigators believe the people they arrested are at the top of the organization, said Insp. Kevin Galvin, from Edmonton police's organized crime branch .

Alberta's Integrated Response to Organized Crime unit, RCMP, Edmonton police and the Metro Edmonton Gang Unit — a joint operation between municipal police and Mounties — were all involved in the investigation.

In spring 2008, the Metro Edmonton Gang Unit charged alleged members of the White Boy Posse at the conclusion of a previous investigation called Operation Goliath.